An ancient gun emplacement at the border between Hong Kong and the Chinese mainland. [Yang Nan/China.org.cn]
![An ancient gun emplacement at the border between Hong Kong and the Chinese mainland. [Yang Nan/China.org.cn]](http://images.china.cn/attachement/jpg/site1007/20081127/000bcdb95f1d0a989e6406.jpg "An ancient gun emplacement at the border between Hong Kong and the Chinese mainland. [Yang Nan/China.org.cn]")